Is usually found in the elbows but it has been seen in the shoulders as well. This disorder causes a painful stiffing of the joint where the dog will be unable to bend its elbow. It is caused by an improper growth of cartilage in the joints and can be hereditary, caused by trauma or improper diet. It can be detected in dogs as young as five to seven months of age. Although it is a genetic disorder, some research has linked high-protein diets to increasing the severity of this disorder.